Beryl is a hexagonal beryllium aluminum cyclosilicate mineral. It is found in hexagonal crystals and has been found in many valuable gem varieties- aquamarine (blue) , emerald (green), Heliodor (yellow), morganite (bubblegum pink), and bixbite (red to fuschia). Beryl has a high hardness of 7.5 to 8 and a glassy to waxy luster. It is a common mineral and has been found in very large single crystals weighing over a ton, which are among the largest single crystals of any known mineral. The world’s largest crystal ever found was discovered at Malakialina, Madagascar and was 3.5 meters wide, over 18 meters long, and weighed nearly 400,000 kilograms.
Beryl is the primary ore of the mineral beryllium, which is a very hard and light metal used in the high performance alloy, x-ray, electronics, and nuclear industries. Beryllium compounds are extremely toxic though beryl itself is totally harmless. Beryllium is a grey metallic metal that is both very light and very hard. Beryllium oxide is the most commonly used compound of beryllium- it is an insulating material in ceramic subjected to extremely high voltages.
Beryl occurs primarily in felsic rocks- most commonly pegmatites and in lesser frequency in miarolytic granites, rhyolites, and some unusual hydrothermal deposits. Gem material though mostly comes from pegmatites with the exception of emerald and bixbite. Pegmatites with large pockets containing aquamarine, Heliodor, and morganite have been found in Pakistan, Afghanistan, Brazil, Namibia, California, Idaho, Colorado, Connecticut, New Hampshire, Massachusetts, Maine, Vietnam, Myanmar, Russia, Italy, and many other lesser-known localities.
Most of the beryl that is used in jewelry and in the mineral specimen trade comes from Brazil or Pakistan where numerous extremely high grade gem pegmatites are heavily mined. The bulk of aquamarine crystals used in wire wraps come from northern Pakistan. These specimens are found in vuggy simple pegmatites containing few other interesting minerals. They are found on a matrix of feldspar and muscovite crystals. Aquamarine of extremely deep blue color is sometimes known as ‘Maxixe Beryl,’ though to be truly of this variety, the beryl must contain some cesium. Aquamarine is often treated with heating to deepen the color.
Heliodor is another kind of beryl found mostly in pegmatites. It is of a yellow to orange color and is most commonly found in Ukraine, Brazil, Vietnam, Madagascar, Tajikistan, Russia, Maine, and Connecticut. Natural Heliodor of extremely high color saturation is extremely rare so much Heliodor facet material and cut stones on the market has been treated with radiation to enhance the color. The best natural Heliodor crystals in the world were found in the Volodarsk-Volynskii pegmatite district in Zhytomyr’ Oblast, Ukraine. Some of these crystals can grow to over a foot in length.
Emerald is a very rare and valuable variety of beryl that is colored deep green by chromium and/or vanadium impurities. It is found in biotite schist and unusual hydrothermal veins rich in carbonates such as calcite or ankerite. Localities that are well known for producing fine emerald are Colombia, Zambia, North Carolina, Brazil, Pakistan, Afghanistan, Madagascar, Russia, South Africa, Australia, Austria, Spain, Egypt, Norway, Montana, Nevada, and Connecticut.
Morganite and bixbite are the two pink varieties of Beryl though the environment and chromophore for each species is distinct. Morganite is a pastel pink to peach colored beryl typically found in pegmatites rich in lithium. Morganite crystals are often flattened on the c-axis. The morganite chromophore is Mn(II). Morganite is rare, but can be found as nice crystals in Maine, California, Afghanistan, Brazil, Madagascar, and Italy.
Bixbite is fuschia colored beryl found in vesicular rhyolite. It is associated with many unusual minerals such as golden topaz, bixbyite (notice confusing name), spessartine, hematite, quartz, and orthoclase. True bixbite is only found in Utah and New Mexico. It is sometimes known as red emerald. Bixbite’s chromophore is Mn(III).